Flexible hoses are well known for conveying gas in a wide variety of applications, both military and civilian.
One standard approach includes providing a flexible tube with insulating material surrounding the same to provide strength and to reduce heat transfer between the flowing gas and the ambient. A disadvantage with this standard design is that often the insulation detracts from the flexibility of the system, adds to weight, and may not contribute significantly to longitudinal tensile and compression strengths of the system.
An attempted standard improvement comprises adding a spring coil to increase strength parameters and perhaps reduce the thickness requirement of the insulation layer depending upon the particular application of the hose assembly.
Where the application requires temperature control, standard hoses are normally coupled to a system that includes a thermocouple device and a controller for sensing the gas temperature before it enters the head end of the hose and applying electric power to the heating elements located before such head end. These systems are somewhat unreliable particularly where the delivery hose branches to a number of users of the gas supply or where the length of hose enables significant exchange between ambient and the flowing gas or where the ambient temperature can vary over a significant range.
One such application where these problems arise is in air supply hoses to crew members of tanks and other military vehicles.
These and other problems are avoided with the hose assembly according to the present invention.